Metal-cutting apparatus

ABSTRACT

An apparatus for cutting sheet metal or the like under emergency conditions includes a bar having a pry surface and a cutting blade at one end thereof, and a cylinder reciprocably slidable thereon. In operation, the point of the cutting blade and the pry surface are rested on the sheet metal. The cylinder is extended, then slid in the direction of the point so as to drive the point through the sheet metal when the cylinder engages a corresponding stop on the bar. Cutting is then accomplished by rocking the bar, using the pry surface as a fulcrum.

United States Patent Bailey et al.

[ 1 Oct. 3, 1972 [54] METAL-CUTTING APPARATUS [22] Filed: Oct. 20, 1971[21] Appl. No.: 190,766

[52] US. Cl. ..30/277, 7/12, 173/126, 30/22 [51 Int. Cl ..B26b 27/00,B25d 17/02 [58] Field of Search....30/l6, 22, 277, 359, 168, 280,30/314, 164.6; 7/12; 145/21, 30.5, 61 F;

[56] References Cited UNITED STATES PATENTS 584,189 6/1897 Nelson..145/61 F 840,580 l/1907 McMillan ..145/61 F 1,174,785 3/1916 Watts.....30/277 1,624,853 4/ 1 927 Winter ..30/168 1,667,360 4/1928 Sweeney..30/314 2,285,386 6/1942 Atwood ..30/314 Primary Examiner-Robert C.Riordon Assistant ExaminerRoscoe V. Parker, Jr. Attorney-Christensen &Sanbom [5 7] ABSTRACT An apparatus for cutting sheet metal or the likeunder emergency conditions includes a bar having a pry surface and acutting blade at one end thereof, and a cylinder reciprocably slidablethereon. In operation, the point of the cutting blade and the prysurface are rested on the sheet metal. The cylinder is extended, thenslid in the direction of the point so as to drive the point through thesheet metal when the cylinder engages a corresponding stop on the bar.Cutting is then accomplished by rocking the bar, using the pry surfaceas a fulcrum.

7 Claims, 6 Drawing Figures METAL-CUTTING APPARATUS FIELD OF THEINVENTION This invention generally relates to apparatus for cuttingsheet metal or the like and finds particular applicability in a devicefor freeing victims of vehicular accidents from a vehicle.

BACKGROUND OF THE INVENTION In vehicular accidents, it is often the casethat access cannot be made to the interior of the vehicle through thevehicles doors or windows due to frame and body distortions. Becausespeedy access to the victims may often mean the difference between lifeand death, some means must be provided for cutting away the body sheetmetal so as to create new access openings.

The prior art has almost exclusively relied on the use of a power sawfor obtaining access. These saws suffer from serious disadvantages.First, their use causes a very loud, rasping noise as the cutting bladeengages the sheet metal. This noise can be very disturbing to both theuser thereof and any onlookers. Second, the cutting action of the sawcreates sparks which are extremely hazardous in situations wheregasoline is leaking. Third, the saw is relatively slow with respect todesired times of access to the victims.

It is therefore an object of this invention to provide a metal-cuttingapparatus which is particularly useful in cutting sheet metal underemergency conditions.

It is a further object of this invention to provide a metal-cuttingapparatus in which the cutting force is entirely obtained as a result ofthe application of manual force thereto.

It is yet another object of this invention to provide such ametal-cutting apparatus which is quiet and speedy in operation, andwhich does not create sparks as the result of the engagement of theapparatus thereof and sheet metal.

It is still a further object of this invention to provide such ametal-cutting apparatus which is readily adaptable to othermetal-working operations, such as prying, bending, and the like.

SUMMARY OF THE INVENTION These objects and others are achieved in oneembodiment of the invention by the provision of an elongated bar havinga cutting blade and a pry surface at one end thereof and additionallyhaving stop means thereon, and an impact member reciprocable with saidbar, including means for engaging said stop means thereof.

BRIEF DESCRIPTION OF THE DRAWINGS The invention can perhaps be bestunderstood by reference to the following portion of the specification,taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a pictorial view showing the use of the metal-cuttingapparatus of this invention;

FIGS. 2 and 3 are side elevation views showing the preferred embodimentsof the invention, with the impact member in extended and retractedpositions, respectively;

FIG. 4 is a front elevation view showing a portion of the apparatus; and

FIGS. 5 and 6 are side elevation views showing alternate,interchangeable metal-working bars for use with the apparatus in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference now to FIG. 1,the metal-cutting apparatus16 of this invention is shown in use. In theillustrated situation, access is desired through the roof 10 of avehicle. In this case, the user of the apparatus 16 has created aninitial opening 12 in the roof 10, then has proceeded to cut the roof 10along the line 14. Both the initial opening 12 and the cut 14 areproduced by appropriate manipulation of the apparatus 16, in a manner tobe described in more detail hereinafter.

With reference now to the embodiment shown in FIGS. 2, 3 and 4, theapparatus 16 includes an elongated bar 18 which is preferably composedof solid steel stock. The bar 18 has pry surfaces 20a, 20b at one endthereof. A cutting blade 22 is welded or otherwise afiixed to the bar 18and includes a first cutting surface 24a which extends from the bar 18to a second, rightangle cutting surface 24b which preferably extendsalong blade 22 in a direction parallel to the axis of bar 18. Cuttingblade 22 also includes a third cutting surface 240 which extends fromcutting surface 24b to a termination point 26 of blade 22. As can beseen, termination point 26 is separated from but substantially coplanarwith pry surfaces 20a, 20b. Preferably, cutting blade 22 is composed ofa hardened carbon steel.

The apparatus also includes a metallic cylinder 28 which is reciprocablyslidable on bar 18. In detail, the upper end of cylinder 28 isterminated by a member 30 which is in threaded engagement therewith andwhich defines an aperture 32 for guiding the reltive reciprocation ofbar 18. The extension of bar 18 is limited by the engagement of theinner surface of member 30 and a corresponding enlarged portion 34 ofbar 18. As the diameter of enlarged portion 34 is chosen to roughlyapproximate the interior diameter of cylinder 28, enlarged portion 34additionally serves as a first guide means for reciprocation.

The other end of cylinder 28 is closed by a solid steel slug 38 which iswelded into place. The retraction of bar 18 is limited by the engagementof slug 38 and a corresponding, enlarged diameter stop 36 on the end ofbar 18. Because of its increased diameter, portion 36 additionallyfunctions as a second guide means for reciprocation.

In operation, the pry surface 20a and point 26 are brought to bearagainst the sheet metal surface which is to be cut. The cylinder 28 isthen slid so that the bar 18 is extended. When the extension is limitedby the engagement of portion 34 and the corresponding member 30, theuser pushes the cylinder 28 at a high rate towards the sheet metalsurface. When the slug 38 therein impacts the corresponding enlargeddiameter portion 36, the impulse resulting from the momentum of cylinder28 is transferred through the bar 18 to pry surface 20a and point 26.This impulse usually drives the point 26 through the sheet metal andfurther serves to enlarge the hole, such as the aperture 12 in FIG. 1,by cutting action of the surface 240. It has been found in practice thatno more than two or three impulses are required to drive the point 26through a sheet metal surface.

To cut along the line 14, the user then rocks the apparatus 16 by usingthe pry surface 20a as a fulcrum and the bar 18 and cylinder 28 as alever. As a result of this rocking motion, the sheet metal is cut by thecutting surfaces 24a and 24b.

If the apparatus is appropriately dimensioned, the use thereof employs alarge mechanical advantage in transmitting the rocking motion exerted bythe user into a cutting action such that practically any sheet metalsurface can be rapidly cut with a minimum of effort. In a practicalembodiment, the bar 18 was about 3 feet long from end to end andcomprised a 1 inch diameter bar of solid steel stock. The cylinder 28comprised a section of 2 inch steel pipe, approximately 2 /2 feet long.Finally, the cutting blade 22 was fashioned from an automobile leafspring and was approximately inches long. The enlarged diameter portion34 was formed by welding a machined bushing onto shaft 18, and theenlarged diameter 36 was formed by appropriate heat treatment thereof.

The metal-cutting apparatus 16 is also useful for cutting throughvehicle door pillars and other more substantial metal surfaces. ln thisregard, both the pry surfaces a and 20b are useful in exerting a pryingforce between a jammed door and its pillar or frame, between the trunkand surrounding sheet metal, or other corresponding surfaces.

The design illustrated is also applicable for receiving tools for othermetal-working operations. With particular reference to FIG. 5, a bar 18'includes enlarged portions 34', 36, which are of similar construction tothe enlarged portions 34, 36 of the bar 18. The bar 18' is reciprocablewithin a coupling member and includes at the upper end thereof a flaredcutting blade 40 having a cutting surface 42 on each side thereof. Thebar 18 is installed in the cylinder 28 by unscrewing the coupling member30 associated with bar 18, removing bar 18, inserting bar 18' andscrewing coupling member 30 onto the corresponding threaded portion ofcylinder 28. The bar 18' is particularly useful for making narrow cutsthrough relatively thick sheet metal surfaces.

Bar 18", useful for prying and bending operations, is illustrated inFIG. 6 and includes enlarged portions 34' 36", a coupling member 30, andtwo pry surfaces 44 on either side of one end thereof. Bar 18" isinserted into the cylinder 28 in a manner identical to bars 18 and 18.

Although the invention has been described particularly in terms of ametal-cutting apparatus for use in obtaining access to vehicles of aemergency conditions, it should be clearly understood by those skilledin the art that the invention is not limited thereto. For example, theinvention finds applicability in any situation where a rough, speedy cutof sheet metal or other like material is required. Therefore, the limitsof the invention are intended to be bounded only by those of theappended claims.

We claim:

1. A metal-cutting apparatus comprising:

a. an elongated bar having a pry surface at a first end thereof andincluding a stop means adjacent a second end thereof,

b. a cutting blade affixed to said elongated bar adjacent said first endthereof, said cutting blade havingja cutting surface separated from butextendgig su stantially parallel to and facing said bar, an a pointadjacent said cutting surface which is substantially co-planar with saidpry surface of said bar, and

c. an impact member reciprocal with said elongated bar which includesmeans for engaging said stop means at some point in reciprocation tothereby transmit an impulse to said elongated bar.

2. An apparatus as recited in claim 1, wherein said cutting bladeincludes a second cutting surface extending from said first cuttingsurface to said point thereof.

3. An apparatus as recited in claim 2, wherein said cutting bladeincludes a third cutting surface extending substantially at a rightangle from said cutting surface to said bar.

4. An apparatus as recited in claim 1, wherein said impact membercomprises a hollow member slidable on said bar, and wherein saidengaging means of said impact member comprises a solid member closing alower end of said hollow member, and said stop means on said barcomprises said second end thereof.

5. An apparatus as recited in claim 4, wherein said bar further includesan enlarged portion thereof between said first and second ends, and saidimpact member further includes a coupling member for closing the upperend of said hollow member, said coupling member defining an aperturetherein for the passage of said bar and including means for engagingsaid enlarged portion thereof so as to limit the extension of said barrelative to said said impact member.

6. An apparatus as recited in claim 5, wherein said bar, said hollowmember, said stop means, said engaging means and said coupling memberare substantially cylindrical.

7. An apparatus as recited in claim 1, wherein said cutting blade iscomposed of a sheet of spring steel which is relatively thin withrespect to the thickness of said bar.

1. A metal-cutting apparatus comprising: a. an elongated bar having apry surface at a first end thereof and including a stop means adjacent asecond end thereof, b. a cutting blade affixed to said elongated baradjacent said first end thereof, said cutting blade having a cuttingsurface separated from but extending substantially parallel to andfacing said bar, and a point adjacent said cutting surface which issubstantially co-planar with said pry surface of said bar, and c. animpact member reciprocal with said elongated bar which includes meansfor engaging said stop means at some point in reciprocation to therebytransmit an impulse to said elongated bar.
 2. An apparatus as recited inclaim 1, wherein said cutting blade includes a second cutting surfaceextending from said first cutting surface to said point thereof.
 3. Anapparatus as recited in claim 2, wherein said cutting blade includes athird cutting surface extending substantially at a right angle from saidcutting surface to said bar.
 4. An apparatus as recited in claim 1,wherein said impact member comprises a hollow member slidable on saidbar, and wherein said engaging means of said impact member comprises asolid member closing a lower end of said hollow member, and said stopmeans on said bar comprises said second end thereof.
 5. An apparatus asrecited in claim 4, wherein said bar further includes an enlargedportion thereof between said first anD second ends, and said impactmember further includes a coupling member for closing the upper end ofsaid hollow member, said coupling member defining an aperture thereinfor the passage of said bar and including means for engaging saidenlarged portion thereof so as to limit the extension of said barrelative to said said impact member.
 6. An apparatus as recited in claim5, wherein said bar, said hollow member, said stop means, said engagingmeans and said coupling member are substantially cylindrical.
 7. Anapparatus as recited in claim 1, wherein said cutting blade is composedof a sheet of spring steel which is relatively thin with respect to thethickness of said bar.